fhandler_serial.cc

cygwin, 著名的在win32下模拟unix操作系统的东东

	if (!ClearCommError (get_handle (), &ev, &st) || !st.cbInQue)
	  break;
      }

  return 0;
}

/* tcsetattr: POSIX 7.2.1.1 */
int
fhandler_serial::tcsetattr (int action, const struct termios *t)
{
  /* Possible actions:
    TCSANOW:   immediately change attributes.
    TCSADRAIN: flush output, then change attributes.
    TCSAFLUSH: flush output and discard input, then change attributes.
  */

  BOOL dropDTR = FALSE;
  COMMTIMEOUTS to;
  DCB ostate, state;
  unsigned int ovtime = vtime_, ovmin = vmin_;
  int tmpDtr, tmpRts;
  tmpDtr = tmpRts = 0;

  termios_printf ("action %d", action);
  if ((action == TCSADRAIN) || (action == TCSAFLUSH))
    {
      FlushFileBuffers (get_handle ());
      termios_printf ("flushed file buffers");
    }
  if (action == TCSAFLUSH)
    PurgeComm (get_handle (), (PURGE_RXABORT | PURGE_RXCLEAR));

  /* get default/last comm state */
  if (!GetCommState (get_handle (), &ostate))
    return -1;

  state = ostate;

  /* -------------- Set baud rate ------------------ */
  /* FIXME: WIN32 also has 14400, 56000, 128000, and 256000.
     Unix also has 230400. */

  switch (t->c_ospeed)
    {
      case B0:	/* drop DTR */
	dropDTR = TRUE;
	state.BaudRate = 0;
	break;
      case B110:
	state.BaudRate = CBR_110;
	break;
      case B300:
	state.BaudRate = CBR_300;
	break;
      case B600:
	state.BaudRate = CBR_600;
	break;
      case B1200:
	state.BaudRate = CBR_1200;
	break;
      case B2400:
	state.BaudRate = CBR_2400;
	break;
      case B4800:
	state.BaudRate = CBR_4800;
	break;
      case B9600:
	state.BaudRate = CBR_9600;
	break;
      case B19200:
	state.BaudRate = CBR_19200;
	break;
      case B38400:
	state.BaudRate = CBR_38400;
	break;
      case B57600:
	state.BaudRate = CBR_57600;
	break;
      case B115200:
	state.BaudRate = CBR_115200;
	break;
      default:
	/* Unsupported baud rate! */
	termios_printf ("Invalid t->c_ospeed %d", t->c_ospeed);
	set_errno (EINVAL);
	return -1;
    }

  /* -------------- Set byte size ------------------ */

  switch (t->c_cflag & CSIZE)
    {
      case CS5:
	state.ByteSize = 5;
	break;
      case CS6:
	state.ByteSize = 6;
	break;
      case CS7:
	state.ByteSize = 7;
	break;
      case CS8:
	state.ByteSize = 8;
	break;
      default:
	/* Unsupported byte size! */
	termios_printf ("Invalid t->c_cflag byte size %d",
			t->c_cflag & CSIZE);
	set_errno (EINVAL);
	return -1;
    }

  /* -------------- Set stop bits ------------------ */

  if (t->c_cflag & CSTOPB)
    state.StopBits = TWOSTOPBITS;
  else
    state.StopBits = ONESTOPBIT;

  /* -------------- Set parity ------------------ */

  if (t->c_cflag & PARENB)
    state.Parity = (t->c_cflag & PARODD) ? ODDPARITY : EVENPARITY;
  else
    state.Parity = NOPARITY;

  state.fBinary = TRUE;     /* Binary transfer */
  state.EofChar = 0;	    /* No end-of-data in binary mode */
  state.fNull = FALSE;      /* Don't discard nulls in binary mode */

  /* -------------- Parity errors ------------------ */
  /* fParity combines the function of INPCK and NOT IGNPAR */

  if ((t->c_iflag & INPCK) && !(t->c_iflag & IGNPAR))
    state.fParity = TRUE;   /* detect parity errors */
  else
    state.fParity = FALSE;  /* ignore parity errors */

  /* Only present in Win32, Unix has no equivalent */
  state.fErrorChar = FALSE;
  state.ErrorChar = 0;

  /* -------------- Set software flow control ------------------ */
  /* Set fTXContinueOnXoff to FALSE.  This prevents the triggering of a
     premature XON when the remote device interprets a received character
     as XON (same as IXANY on the remote side).  Otherwise, a TRUE
     value separates the TX and RX functions. */

  state.fTXContinueOnXoff = TRUE;     /* separate TX and RX flow control */

  /* Transmission flow control */
  if (t->c_iflag & IXON)
    state.fOutX = TRUE;   /* enable */
  else
    state.fOutX = FALSE;  /* disable */

  /* Reception flow control */
  if (t->c_iflag & IXOFF)
    state.fInX = TRUE;    /* enable */
  else
    state.fInX = FALSE;   /* disable */

  /* XoffLim and XonLim are left at default values */

  state.XonChar = (t->c_cc[VSTART] ? t->c_cc[VSTART] : 0x11);
  state.XoffChar = (t->c_cc[VSTOP] ? t->c_cc[VSTOP] : 0x13);

  /* -------------- Set hardware flow control ------------------ */

  /* Disable DSR flow control */
  state.fOutxDsrFlow = FALSE;

  /* Some old flavors of Unix automatically enabled hardware flow
     control when software flow control was not enabled.  Since newer
     Unices tend to require explicit setting of hardware flow-control,
     this is what we do. */

  /* RTS/CTS flow control */
  if (t->c_cflag & CRTSCTS)
    {							/* enable */
      state.fOutxCtsFlow = TRUE;
      state.fRtsControl = RTS_CONTROL_HANDSHAKE;
    }
  else
    {							/* disable */
      state.fRtsControl = RTS_CONTROL_ENABLE;
      state.fOutxCtsFlow = FALSE;
      tmpRts = TIOCM_RTS;
    }

  if (t->c_cflag & CRTSXOFF)
    state.fRtsControl = RTS_CONTROL_HANDSHAKE;

  /* -------------- DTR ------------------ */
  /* Assert DTR on device open */

  state.fDtrControl = DTR_CONTROL_ENABLE;

  /* -------------- DSR ------------------ */
  /* Assert DSR at the device? */

  if (t->c_cflag & CLOCAL)
    state.fDsrSensitivity = FALSE;  /* no */
  else
    state.fDsrSensitivity = TRUE;   /* yes */

  /* -------------- Error handling ------------------ */
  /* Since read/write operations terminate upon error, we
     will use ClearCommError() to resume. */

  state.fAbortOnError = TRUE;

  /* -------------- Set state and exit ------------------ */
  if (memcmp (&ostate, &state, sizeof (state)) != 0)
    SetCommState (get_handle (), &state);

  set_r_binary ((t->c_iflag & IGNCR) ? 0 : 1);
  set_w_binary ((t->c_oflag & ONLCR) ? 0 : 1);

  if (dropDTR == TRUE)
    {
      EscapeCommFunction (get_handle (), CLRDTR);
      tmpDtr = 0;
    }
  else
    {
      /* FIXME: Sometimes when CLRDTR is set, setting
      state.fDtrControl = DTR_CONTROL_ENABLE will fail.  This
      is a problem since a program might want to change some
      parameters while DTR is still down. */

      EscapeCommFunction (get_handle (), SETDTR);
      tmpDtr = TIOCM_DTR;
    }

  rts = tmpRts;
  dtr = tmpDtr;

  /*
  The following documentation on was taken from "Linux Serial Programming
  HOWTO".  It explains how MIN (t->c_cc[VMIN] || vmin_) and TIME
  (t->c_cc[VTIME] || vtime_) is to be used.

  In non-canonical input processing mode, input is not assembled into
  lines and input processing (erase, kill, delete, etc.) does not
  occur. Two parameters control the behavior of this mode: c_cc[VTIME]
  sets the character timer, and c_cc[VMIN] sets the minimum number of
  characters to receive before satisfying the read.

  If MIN > 0 and TIME = 0, MIN sets the number of characters to receive
  before the read is satisfied. As TIME is zero, the timer is not used.

  If MIN = 0 and TIME > 0, TIME serves as a timeout value. The read will
  be satisfied if a single character is read, or TIME is exceeded (t =
  TIME *0.1 s). If TIME is exceeded, no character will be returned.

  If MIN > 0 and TIME > 0, TIME serves as an inter-character timer. The
  read will be satisfied if MIN characters are received, or the time
  between two characters exceeds TIME. The timer is restarted every time
  a character is received and only becomes active after the first
  character has been received.

  If MIN = 0 and TIME = 0, read will be satisfied immediately. The
  number of characters currently available, or the number of characters
  requested will be returned. According to Antonino (see contributions),
  you could issue a fcntl(fd, F_SETFL, FNDELAY); before reading to get
  the same result.
  */

  if (t->c_lflag & ICANON)
    {
      vmin_ = 0;
      vtime_ = 0;
    }
  else
    {
      vtime_ = t->c_cc[VTIME] * 100;
      vmin_ = t->c_cc[VMIN];
    }

  debug_printf ("vtime %d, vmin %d", vtime_, vmin_);

  if (ovmin == vmin_ && ovtime == vtime_)
    return 0;

  memset (&to, 0, sizeof (to));

  if ((vmin_ > 0) && (vtime_ == 0))
    {
      /* Returns immediately with whatever is in buffer on a ReadFile();
	 or blocks if nothing found.  We will keep calling ReadFile(); until
	 vmin_ characters are read */
      to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD;
      to.ReadTotalTimeoutConstant = MAXDWORD - 1;
    }
  else if ((vmin_ == 0) && (vtime_ > 0))
    {
      /* set timeoout constant appropriately and we will only try to
	 read one character in ReadFile() */
      to.ReadTotalTimeoutConstant = vtime_;
      to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD;
    }
  else if ((vmin_ > 0) && (vtime_ > 0))
    {
      /* time applies to the interval time for this case */
      to.ReadIntervalTimeout = vtime_;
    }
  else if ((vmin_ == 0) && (vtime_ == 0))
    {
      /* returns immediately with whatever is in buffer as per
	 Time-Outs docs in Win32 SDK API docs */
      to.ReadIntervalTimeout = MAXDWORD;
    }

  debug_printf ("ReadTotalTimeoutConstant %d, ReadIntervalTimeout %d, ReadTotalTimeoutMultiplier %d",
		to.ReadTotalTimeoutConstant, to.ReadIntervalTimeout, to.ReadTotalTimeoutMultiplier);
  int res = SetCommTimeouts (get_handle (), &to);
  if (!res)
    {
      system_printf ("SetCommTimeout failed, %E");
      __seterrno ();
      return -1;
    }

  return 0;
}

/* tcgetattr: POSIX 7.2.1.1 */
int
fhandler_serial::tcgetattr (struct termios *t)
{
  DCB state;

  /* Get current Win32 comm state */
  if (GetCommState (get_handle (), &state) == 0)
    return -1;

  /* for safety */
  memset (t, 0, sizeof (*t));

  /* -------------- Baud rate ------------------ */

  switch (state.BaudRate)
    {
      case 0:
	/* FIXME: need to drop DTR */
	t->c_cflag = t->c_ospeed = t->c_ispeed = B0;
	break;
      case CBR_110:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B110;
	break;
      case CBR_300:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B300;
	break;
      case CBR_600:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B600;
	break;
      case CBR_1200:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B1200;
	break;
      case CBR_2400:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B2400;
	break;
      case CBR_4800:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B4800;
	break;
      case CBR_9600:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B9600;
	break;
      case CBR_19200:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B19200;
	break;
      case CBR_38400:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B38400;
	break;
      case CBR_57600:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B57600;
	break;
      case CBR_115200:
	t->c_cflag = t->c_ospeed = t->c_ispeed = B115200;
	break;
      default:
	/* Unsupported baud rate! */
	termios_printf ("Invalid baud rate %d", state.BaudRate);
	set_errno (EINVAL);
	return -1;
    }

  /* -------------- Byte size ------------------ */

  switch (state.ByteSize)
    {
      case 5:
	t->c_cflag |= CS5;
	break;
      case 6:
	t->c_cflag |= CS6;
	break;
      case 7:
	t->c_cflag |= CS7;
	break;
      case 8:
	t->c_cflag |= CS8;
	break;
      default:
	/* Unsupported byte size! */
	termios_printf ("Invalid byte size %d", state.ByteSize);
	set_errno (EINVAL);
	return -1;
    }

  /* -------------- Stop bits ------------------ */

  if (state.StopBits == TWOSTOPBITS)
    t->c_cflag |= CSTOPB;

  /* -------------- Parity ------------------ */

  if (state.Parity == ODDPARITY)
    t->c_cflag |= (PARENB | PARODD);
  if (state.Parity == EVENPARITY)
    t->c_cflag |= PARENB;

  /* -------------- Parity errors ------------------ */

  /* fParity combines the function of INPCK and NOT IGNPAR */
  if (state.fParity == TRUE)
    t->c_iflag |= INPCK;
  else
    t->c_iflag |= IGNPAR;	/* not necessarily! */

  /* -------------- Software flow control ------------------ */

  /* transmission flow control */
  if (state.fOutX)
    t->c_iflag |= IXON;

  /* reception flow control */
  if (state.fInX)
    t->c_iflag |= IXOFF;

  t->c_cc[VSTART] = (state.XonChar ? state.XonChar : 0x11);
  t->c_cc[VSTOP] = (state.XoffChar ? state.XoffChar : 0x13);

  /* -------------- Hardware flow control ------------------ */
  /* Some old flavors of Unix automatically enabled hardware flow
     control when software flow control was not enabled.  Since newer
     Unices tend to require explicit setting of hardware flow-control,
     this is what we do. */

  /* Input flow-control */
  if ((state.fRtsControl == RTS_CONTROL_HANDSHAKE) &&
      (state.fOutxCtsFlow == TRUE))
    t->c_cflag |= CRTSCTS;
  if (state.fRtsControl == RTS_CONTROL_HANDSHAKE)
    t->c_cflag |= CRTSXOFF;

  /* -------------- CLOCAL --------------- */
  /* DSR is only lead toggled only by CLOCAL.  Check it to see if
     CLOCAL was called. */
  /* FIXME: If tcsetattr() hasn't been called previously, this may
     give a false CLOCAL. */

  if (state.fDsrSensitivity == FALSE)
    t->c_cflag |= CLOCAL;

  /* FIXME: need to handle IGNCR */
#if 0
  if (!get_r_binary ())
    t->c_iflag |= IGNCR;
#endif

  if (!get_w_binary ())
    t->c_oflag |= ONLCR;

  t->c_cc[VTIME] = vtime_ / 100;
  t->c_cc[VMIN] = vmin_;

  debug_printf ("vmin_ %d, vtime_ %d", vmin_, vtime_);

  return 0;
}

void
fhandler_serial::fixup_after_fork (HANDLE parent)
{
  if (get_close_on_exec ())
    this->fhandler_base::fixup_after_fork (parent);
  overlapped_setup ();
  debug_printf ("io_status.hEvent %p", io_status.hEvent);
}

void
fhandler_serial::fixup_after_exec (HANDLE)
{
  overlapped_setup ();
  debug_printf ("io_status.hEvent %p", io_status.hEvent);
  return;
}

int
fhandler_serial::dup (fhandler_base *child)
{
  fhandler_serial *fhc = (fhandler_serial *) child;
  overlapped_setup ();
  fhc->vmin_ = vmin_;
  fhc->vtime_ = vtime_;
  return fhandler_base::dup (child);
}